A new patent filing discovered by AppleInsider provides some of the first public evidence that Apple is indeed exploring carbon fiber-like enclosures for future product designs, corroborating an earlier report on the matter.

In the 9-page filing published for the first time this week, the Mac maker explains that carbon fiber reinforced plastic, also referred to as carbon fiber composites, provide a very strong, lightweight material for forming housings for electronic devices and portable computers.

The company describes in some detail how these composites are traditionally formed by laying sheets of carbon fiber material into a mold that is the shape of the desired product, which is then filled with thermosetting resin that is "cured" and cooled until the thermoplastic resin is below its glass transition temperature, thereby allowing the material to maintain the shape of the mold.

There are also some alternative methods to forming carbon fiber composites, though Apple takes issue with all of them because the methods produce composites that are almost always black in color with carbon fibers visible on the composite surface, which together threaten to dictate the aesthetic of products for which they're employed.

"In addition, the fibers (either as a unidirectional, woven, or nonwoven substrate) are typically variable in their construction and therefore are variable in their surface presentation," the company says. "As a result, the resulting carbon fiber composite can have cosmetic imperfections that reduce the aesthetic appearance of the molded article formed therefrom. Further, carbon fiber composites, often being black, provide a narrow range of surface appearance to the molded article and therefore may give a 'tired,' unexciting look."

Apple's fairly detailed and technical solution to the problem is described as such:

A composite laminate having an improved cosmetic surface is presented herein. The composite laminate includes a plurality of sheets of preimpregnated material, or prepreg, stacked one over another and a scrim layer provided on an exterior surface of the sheets of prepreg. The scrim layer and the sheets of prepreg form a composite laminate whereby the scrim layer constitutes an outer, exposed surface of the composite laminate. Each sheet of prepreg is made from fibers preimpregnated with resin, and the fibers of the prepreg may be substantially parallel or woven carbon fibers. The scrim layer may be a glass fiber or carbon fiber scrim, or veil, that has absorbed resin from the sheets of prepreg during a molding process. In another embodiment, the composite laminate includes a plurality of sheets of prepreg stacked one over another and first and second scrim layers provided on opposing exterior surfaces of the sheets of prepreg, whereby the sheets of prepreg are sandwiched between the first and second scrim layers. The first and second scrim layers constitute exposed surfaces of the composite laminate.

Enclosing a carbon fiber composite in a thin scrim made of glass fiber -- which is less stiff than carbon fiber -- would offer improved impact resistance over a similar composite laminate incorporating a carbon fiber scrim and would also hide the reinforcing fibers of the carbon fiber prepreg sheets, Apple claims.

"Since scrim absorbs resin of the composite, scrim takes on the cosmetic properties and color of resin. Also [...] scrim is very thin, and it is translucent, and the underlying fibers of composite are partially visible therethrough," the company explains in more detail. "The combination of resin and scrim forming scrim layer imparts a depth to surface of composite laminate, thereby providing an improved cosmetic surface of a molded article formed therefrom that is not only consistent in appearance, but is also aesthetically pleasing."

As such, Apple concludes that the "embodiments of the present invention described herein provide a designer with the opportunity to produce molded articles that have the advantageous properties of carbon fiber composites, without being limited to its black color or its imperfections in appearance."

Readers may recall that last November AppleInsider cited people familiar with Apple's portable computing plans who noted that the company has been looking into substituting carbon fiber parts for certain structural components of its notebook products that are currently cast from heavier aircraft-grade aluminum.

A breakdown of the Air's weight provided by iFixit.

In particular, the Mac maker was said to be exploring the idea specifically for the MacBook Air by which it would replacing the Air's lower aluminum case, or bottom cover, with one constructed from carbon fiber.

The move would reportedly raise production costs but shave upwards of a 100 grams off the ultra-thin notebook, dropping its weight from a hair over 3 pounds (or 1363 grams) to 2.78 pounds (or 1263 grams). At the time, a pre-production unit showcasing the new part was said to be floating around in one of the company's labs, looking identical to the existing Air with the exception of the carbon fiber bottom, which, contrary to Apple's liking, appeared in the material's native black.

A new patent filing discovered by AppleInsider provides some of the first public evidence that Apple is indeed exploring carbon fiber-like enclosures for future product designs, corroborating an earlier report on the matter.

So...Apple is patenting a method for forming carbon fiber cases? Does anybody know how these "method" patents work?

Could another company change the composition of the resin or the scrim and claim that it is outside of the patent? Or is Apple attempting to lock up the idea of using a cosmetic glass fiber surface over top of carbon fiber?

I generally understand what Apple want's to do, but I don't understand the scope of the expected/intended patent protection...

The new MacBook aluminum enclosures might be pricier to mill but that process saves lots of money in the assembly process which require fewer parts to manufacture. So in the end the cost should be the same.

I don't get it-- wasn't one of the purposes of using aluminum in the MacBooks to make them recyclable? Can't imagine it is too easy to recycle carbon fiber laminates! But in something small like an iPod/iPhone it could make sense, were the finished product to be more impact and scratch resistant.

I don't know... Aluminum may be a cheaper material, but the machining process certainly isn't. Carbon fiber, like fiberglass, is a pretty simple process in terms of manufacturing.

Working with carbon fiber is nasty. I don't like being around it at all - I worked in aerospace. If Apple is trying to be "green," this would not be the way to go. You need to be covered head to toe to work with the stuff safely. If the carbon fibers get in your skin, it doesn't ever come out. The resins used are also nasty and you don't want them touching your skin. I'd say no thanks to something that is in that close proximity to me on a daily basis.

Carbon fiber doesn't have to be glossy or cheap looking. High-end tripods and monopods for photography/video, lightweight performance car parts, even boat hulls can be made from carbon fiber, and they aren't glossy. They are only glossy if it's going to be for display purposes. In which case the resin can possibly discolor over time, like carbon fiber hoods and spoilers some people put in their cars.

Since the article mentioned cooling the resin below its Tg (edit: and it says it is a thermoplastic resin) , it sounds more like a thermoplastic resin to me. Still tough to recycle with all those carbon fibers in it.

Not sure how patentable this is, given the fact that the outer layers have a name, scrim layers, it seems as if this would be a standard process by now. Maybe the patent is just for computer cases or for protection against patent trolls.

That is one helluva lot of work to loose 100 grams! For a netbook / tablet /iphone / air type device with built in g3 / g4 technology aluminum is problematic, is it not? The research is an investment in future products, I am sure.

That is one helluva lot of work to loose 100 grams! For a netbook / tablet /iphone / air type device with built in g3 / g4 technology aluminum is problematic, is it not? The research is an investment in future products, I am sure.

I totally agree. This seems much more likely. We should expect to see this
type of enclosure on a new iTablet or iPhone instead of larger products
like the MBA, etc.

Journalism is publishing what someone doesn't want us to know; the rest is propaganda.-Horacio Verbitsky (el perro), journalist (b. 1942)

"In addition, the fibers (either as a unidirectional, woven, or nonwoven substrate) are typically variable in their construction and therefore are variable in their surface presentation," the company says. "As a result, the resulting carbon fiber composite can have cosmetic imperfections that reduce the aesthetic appearance of the molded article formed therefrom.
...

Also [...] scrim is very thin, and it is translucent, and the underlying fibers of composite are partially visible therethrough," the company explains in more detail. "The combination of resin and scrim forming scrim layer imparts a depth to surface of composite laminate, thereby providing an improved cosmetic surface of a molded article formed therefrom that is not only consistent in appearance, but is also aesthetically pleasing."

I love the use of "therethrough", "therefore", "thereby", and "therefrom" in such
close proximity to one another!

Journalism is publishing what someone doesn't want us to know; the rest is propaganda.-Horacio Verbitsky (el perro), journalist (b. 1942)

Why does everything made from Carbon fiber has to have a freggin glossy cheesey plastic look?

"Carbon Fiber" refers to the type of fabric used, and by itself is flexible and not suitable for structures such as computer cases or Formula 1 cars. It is generally used as a reinforcement embedded within a plastic resin, much like steel bars in concrete. The full name of the composite material is "Carbon Fiber Reinforced Plastic".

The usual glossy plastic look comes from the fact that the surface is in fact, plastic.

The only product where this carbon fiber enclosure would make sense would be with the iPhone. It would be better than the current fragile plastic enclosure. Unlike Al, it would not interfere with all the antennas that the product has, including GSM, WCDMA/3G, WiFi, Bluetooth and even GSP.

Apple has never really stated that the plastic back of the device actually is "plastic". In fact, they filed a very interesting patent, #20060268528 for an unusually strong substance described as a ceramic-like hybrid of zirconia and Yttrium hybrid with an added silicon coating applied “on the exterior surface to prevent cracking and protect the ceramic shell from undesirable forces as for example when the ceramic shell is dropped.”

Since the article mentioned cooling the resin below its Tg (edit: and it says it is a thermoplastic resin) , it sounds more like a thermoplastic resin to me. Still tough to recycle with all those carbon fibers in it.

I see were you are coming from ('Tg', I thought the same as you in the beginning), but at the same time they call it prepregs in their filing which would hint to thermosetting resin?

Anyway recycling will be a bitch, unless you call it quits and just decompose it thermally.

Since the article mentioned cooling the resin below its Tg (edit: and it says it is a thermoplastic resin) , it sounds more like a thermoplastic resin to me. Still tough to recycle with all those carbon fibers in it.

It mentions both thermosetting and thermoplastic in the same sentence. I think Appleinsider is rather confused. Resins are thermosetting.

Besides, carbon fiber is old news. If Apple wants to do better and have a recyclable material to boot, they should go with 3D carbon-carbon. Very energy-intensive and expensive to manufacture, but can't do much better than 3D C-C.

I love the use of "therethrough", "therefore", "thereby", and "therefrom" in such
close proximity to one another!

Exact and concise expression of ideas make the use of such words requisite and therewith comes clear understanding. Clear understanding is fundamental to fruitful intellectual discourse and thereof conflict is avoided. The ability to impart unambiguous information is an art of reduction and exactitude and therein lies the secret of the great communicators.
There!

I like those machines with the carbon fiber bottom. The two tone look is stylish. But is shaving 100 grams off the current weight worth the expense?

How much work it takes doesn't seem to be a problem to them. How much work do they do to make their aluminum cases? Don't they start from a 3lb blank?

But I'm not sure if it's a viable material here. In a sheet, aluminum is a lot stiffer than carbon fiber, I think you'd have to add more bracing (and thickness) to make them fill similarly stiff.

Quote:

Originally Posted by Davejay

No, no, no, no, no! I like the aluminum! Don't go back to anything that looks plasticky!

The resin is plastic, but the surface finish can be different.

Quote:

Originally Posted by ulfoaf

Working with carbon fiber is nasty. I don't like being around it at all - I worked in aerospace. If Apple is trying to be "green," this would not be the way to go. You need to be covered head to toe to work with the stuff safely. If the carbon fibers get in your skin, it doesn't ever come out. The resins used are also nasty and you don't want them touching your skin. I'd say no thanks to something that is in that close proximity to me on a daily basis.

Of course, breathing aluminum dust is really bad too ....

Machining aluminum doesn't make dust though, it makes chips, even the fine finish pass probably isn't considered dust, and would be kept down just by the flood coolant. Maybe the final texture with whatever blasting they use makes dust, but that can be contained pretty easily.

Quote:

Originally Posted by marokero

Carbon fiber doesn't have to be glossy or cheap looking. High-end tripods and monopods for photography/video, lightweight performance car parts, even boat hulls can be made from carbon fiber, and they aren't glossy. They are only glossy if it's going to be for display purposes. In which case the resin can possibly discolor over time, like carbon fiber hoods and spoilers some people put in their cars.

I wonder if they don't bother to have UV protection in the resin. A simple clear coat might solve that. I think that might be partly a mistake on the buyer's part too, they keep it "naked" to show off that they paid for carbon fiber parts, and that might be the culprit. A layer or two of clear coat can give a look of depth, better UV protection and probably better scratch & scuff protection too.

"Carbon Fiber" refers to the type of fabric used, and by itself is flexible and not suitable for structures such as computer cases or Formula 1 cars. It is generally used as a reinforcement embedded within a plastic resin, much like steel bars in concrete. The full name of the composite material is "Carbon Fiber Reinforced Plastic".

The usual glossy plastic look comes from the fact that the surface is in fact, plastic.

Exactly. And IMO, carbon fiber looks absolutely gaudy, mostly due to the woven nature of the fiber which gives it that 3D-ish shiny appearance. Add in the clear plastic resin, which is the most common applique for carbon fiber, and it looks downright ugly. I really don't understand the big deal over it. Sure, its strong, but you have to pair the carbon fiber with another substance to give it a lasting form. Therefore, Apple's implementation would surely be "carbon fiber reinforced [insert material here]." Definitely not plastic.

How much work it takes doesn't seem to be a problem to them. How much work do they do to make their aluminum cases? Don't they start from a 3lb blank?

But I'm not sure if it's a viable material here. In a sheet, aluminum is a lot stiffer than carbon fiber, I think you'd have to add more bracing (and thickness) to make them fill similarly stiff.

The resin is plastic, but the surface finish can be different.

Machining aluminum doesn't make dust though, it makes chips, even the fine finish pass probably isn't considered dust, and would be kept down just by the flood coolant. Maybe the final texture with whatever blasting they use makes dust, but that can be contained pretty easily.

I wonder if they don't bother to have UV protection in the resin. A simple clear coat might solve that. I think that might be partly a mistake on the buyer's part too, they keep it "naked" to show off that they paid for carbon fiber parts, and that might be the culprit. A layer or two of clear coat can give a look of depth, better UV protection and probably better scratch & scuff protection too.

Apple seems to have a very poor grasp of the technology and its capabilities. More often than not, carbon fiber products have an "exposed" appearance by choice, because people want others to know that it is carbon fiber. If Apple is faulting the materials and fabrication it must certainly be because they are talking to the wrong people. Everything from aircraft to formula one cars to laptop cases have been made from carbon fiber and, with quality workmanship, they are a work of art. Don't like the look? No problem. Aircraft have any number of potential finishes available over the structural component. Apple seem to have no grasp of the strength of the material in view of the number of layers in the filing.

There is absolutely nothing new in what Apple have stated. Nothing at all. They look like fools for claiming that it is.

exact and concise expression of ideas make the use of such words requisite and therewith comes clear understanding. Clear understanding is fundamental to fruitful intellectual discourse and thereby conflict is avoided. The ability to impart unambiguous information is an art of reduction and exactitude and therein lies the secret of the great communicators.
There!

Exactly. And IMO, carbon fiber looks absolutely gaudy, mostly due to the woven nature of the fiber which gives it that 3D-ish shiny appearance. Add in the clear plastic resin, which is the most common applique for carbon fiber, and it looks downright ugly. I really don't understand the big deal over it. Sure, its strong, but you have to pair the carbon fiber with another substance to give it a lasting form. Therefore, Apple's implementation would surely be "carbon fiber reinforced [insert material here]." Definitely not plastic.

What other material would it reinforce if not plastic? Plastics are a huge class of materials that I wonder if any alternative suggestions you would provide would also be a form of plastic.

And if you don't like the shine, it's easy to give it a more matte appearance or other finish or texture. Your response makes me wonder about those people that go orgasmic over Apple's shiny screens.